\(\renewcommand\AA{\text{Å}}\)
Mass¶
periodictable.mass
¶
Adds average mass for the elements:
- mass, mass_units (u)
The molar mass averaged over natural isotope abundance.
Adds mass and abundance information for isotopes:
- mass, mass_units (u)
The molar mass of the individual isotope.
- abundance, abundance_units (%)
Natural abundance for the isotope.
Atomic Weights and Isotopic Composition 1.
The atomic weights are available for elements 1 through 112, 114, & 116 and isotopic compositions or abundances are given when appropriate. The atomic weights data were published by Coplen 2 in Atomic Weights of the Elements 1999, (and include changes reported from the 2001 review in Chem. Int., 23, 179 (2001)) and the isotopic compositions data were published by Rosman 3 and Taylor 4 in Isotopic Compositions of the Elements 1997. The relative atomic masses of the isotopes data were published by Audi 5 and Wapstra 6 in the 1995 Update To The Atomic Mass Evaluation.
This data has been compiled from the above sources for the user’s convenience and does not represent a critical evaluation by the NIST Physics Laboratory. http://physics.nist.gov/PhysRefData/Compositions/
Neutron mass from NIST Reference on Constants, Units, and Uncertainty http://physics.nist.gov/cuu/index.html
- 1
Coursey. J. S., Schwab. D. J., and Dragoset. R. A., NIST, Physics Laboratory, Office of Electronic Commerce in Scientific and Engineering Data.
- 2
Coplen. T. B. : U.S. Geological Survey, Reston, Virginia, USA.
- 3
Rosman. K. J. R. : Department of Applied Physics, Curtin University of Technology, Australia.
- 4
Taylor. P. D. P. : Institute for Reference Materials and Measurements, European Commission, Belgium.
- 5
Audi. G. : Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, Orsay Campus, France.
- 6
Wapstra. A. H. : National Institute of Nuclear Physics and High-Energy Physics, Amsterdam, The Netherlands.
-
periodictable.mass.
abundance
(isotope)¶ Natural abundance.
- Parameters
isotope : Isotope
- Returns
abundance : float | %
- Reference:
Coursey. J. S., Schwab. D. J, and Dragoset. R. A., NIST Atomic Weights and Isotopic Composition Database.
-
periodictable.mass.
init
(table, reload=False)¶ Add mass attribute to period table elements and isotopes
-
periodictable.mass.
mass
(isotope)¶ Atomic weight.
- Parameters
isotope : Isotope
- Returns
- massfloat | u
Atomic weight of the element.
- Reference:
Coursey. J. S., Schwab. D. J, and Dragoset. R. A., NIST Atomic Weights and Isotopic Composition Database.